Literary usage of Snitcher

Below you will find example usage of this term as found in modern and/or classical literature:

1.Raymond Mhlaba's Personal Memoirs: Reminiscing from Rwanda and Uganda by Raymond Mhlaba, Thembeka Mufamadi, Human Sciences Research Council, Robben Island Museum (2001)"We wrote to Advocate Harry snitcher who was based in Cape Town. ... snitcher was
also a member of the Party. He was sympathetic to our case. ..."

2.A Glossary of Words Used in the Neighbourhood of Sheffield by Sidney Oldall Addy (1888)"A large stone on the right-hand side of the road, just above the inn at Hollow
Meadows, is called The Snip. It means ' the cut-off piece.' snitcher, sb. the ..."

4.A History of Vagrants and Vagrancy, and Beggars and Begging by Charles James Ribton-Turner (1887)"... the snitcher follows the loser, and asks him what he will give him (the
snitcher) if he puts him in the way of recovering his money? PRAD" BORROWERS. ..."